\documentclass{article}

\usepackage[export]{adjustbox}
\usepackage{booktabs}
\usepackage{calc}
\usepackage{rotating}
\usepackage{multirow}
\usepackage[margin=0.5cm, hoffset=-0.5cm, paperwidth=15cm, paperheight=10.8cm]{geometry}

\begin{document}
\makebox[1\textwidth]{%\parbox{\dimexpr\linewidth-0.5\fboxsep-0.5\fboxrule}{ 
											\parbox{\textwidth}{
											\centering
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_1980_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_1981_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_1982_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_1983_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_1984_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_1985_rlwage.png}\\
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_1986_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_1987_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_1988_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_1989_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_1990_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_1991_rlwage.png}\\
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_1992_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_1993_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_1994_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_1995_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_1996_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_1997_rlwage.png}\\
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_1998_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_1999_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_2000_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_2001_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_2002_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_2003_rlwage.png}\\
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_2004_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_2005_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_2006_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_2007_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_2008_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_2009_rlwage.png}\\
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_2010_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_2011_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_2012_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_2013_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_2014_rlwage.png}
											\adjincludegraphics[width=0.16\textwidth,trim={0.5cm 0.5cm 0.5cm 0.5cm},clip]{CHmen_2015_rlwage.png}\\
											%\vspace{0.5cm}
											%\scriptsize{Kernel density estimates for men's real log wages (\$2015)}
											}
}
\end{document}